Electric pocket lamp



0. PLETSCHER. ELECTBIC POCKET LAMP. APPLICATlON man OCT-17,8917.

Patented Jan. 10, 1922.

invention, sue.

PATENT oi-rice,

OTTO PLETSCHER, 0F ALBISR IEDEN, SWITZERW.

ELECTRIC EGCKET LA.'MP.

Specification of Letters Patent.

Patented Jan. 10, 1922.

Application fired October 27, 1917. Serial No. 198,853.

To aZZ whom it may concern Benit known that I, O'rro PLnrsoHnR, a citizen of the Republic of Switzerland, residing at Albisrieden, Canton of Zurich, Switzerland, have invented certain new and use ful Imp: vements in Electric Pocket Lamps; and I do hereby declare the following to be id exact description of the as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to letters or fi ures of reference marked thereon, which form a part of this specification.

It is known that in electric pocket lamps,

the current for which is supplied by a hand driven dynamo, it is necessary to have, for instance, a spring" mechanism for the pun of rendering the driving of the dynamo uniform; possible, and of obtaining light even when the reciprocating winding movement has ceased. The reason that such an auxiliary device has been required, was that it was impossible to make the rotating part of the dynamo heavy enough to utilize it as a fly-Wheel that would render the working and the running of the dynamo soiliciently uniform, since it was considered necessary, in connection with the driving, to arrange thiespindle of the dynamo in the direction of the width of the pocket lamp. As however the pocket lamp had to be seized and held with one hand, whilst the same hand operated the dynamo, the width of the pocket'lamp, and therefore the length of the dynamo, measured in its axial'direiy tion, were also limited.

' This invention relates to an electric pocket lamp in which no auxiliary device is required for rendering the driving or running of the dynamo uniform, and the Width of the pocket lamp forms no limitation for the length of the dynamo, measured in its axial direction. In the lamp according to this invention, the longitudinal axis of the dynamo is situated in the longitudinal direction of the pocket lamp casing, the dynamo has a field magnet acting as a fly-wheel, and the said field magnet can be rotated by means of a bevel gear at one end of the casing by means of a lever movable towards the latter and rotatable about a pin normal to the longitudinal direction of the casing, while the incandescent lamp is connected to the stationary armature.

A preferable construction is to make the casing cylindrical and to provide it at the bottom with a projecting part at one side in which is arranged the driving means for the field magnet, the driving lever being also arranged at the bottom part of the casing at the side opposite the projecting part, so that the latter, when the'lever is operated with the thumb, offers a support against any change of position of the casing in the hand. A

A construction according to this invention is illustrated, by Way of example, in the accompanying (ire-wing, in which:

Fig. i shows the same in side elevation;

Fig. 2 is a longitudinal section;

Fig. 3 is a bottom view, with the cover removed;

Fig. 4e illustrates a section on the line 0" Fig. 2;

shows a section on the line L-I the two ends 15 oi the winding is carried to a terminal 18, the bottom plate being pro vided with a pin 5 resting in a plate 7. The latter is secured to a widened part 19 of the cylindrical casing 10. ihe hollow pin 6 has a square end mounted in a plate 7 secured to the upper part of the cylindrical casing 10. This upper part is covered by acap 9 carrying the incandescent bulb 20 with a lens 21 in front of it. The bulb is supplied with current through the other wire 15 which leads to a spring-controlled tongue 22 insulated from, and secured to the upper plate 7* by a terminal 17. On the ,in 5 is rotatably mounted at one side of the ower plate 7 a pinion 23 engaging with a toothed wheel 24; mounted between the casing itself and a bracket 25 secured to the plate 7. On the some spindle as the toothed wheel 24, is also mounted a pinion 26 engagthe contrary secured to the toothed wheel 27.. With the bevel'wheel 29 engages abevel turns t 24 whic wheel segment 30 secured to a lever 31 rotatable about a pin 32 and held in contact with the casing 10 by means of a locking button 34 in opposition to the action of a spring 33. When the button 34 is turned, out of the osition shown inFig. 1, through an an le of 90",'thelever 31 will be released, and t e spring 33 will bring it into the dotted pos1tion shown,in Fig-. 1.

' The pinion 23 issecured-to a disc 8 secured to the lowest pair of ma ets of a series 11 by means of screws. he upper pair of magnets 11 is in its turn connected to a disc 8 provided with a neck whichis rotatably mounted about the cylindrical-portion of the pin .6-.-" The in ets of each them an interval 13 (Figure 4). The object of'th'e ring on the lever 31 is to facilitate the manipulation of the lever; thus for a short thumb the position shown on the drawing will be used, and foralonger thumb the ring will be. foldedupwards towards. the

button 34. v 4 v 1 in order to -light the bulb of the pocket lamp, the button 34 is turned through 90,

go, that the lever 31 springs into the dotted position in Figure 1. The lamp is then surrounded by the four fingers, whilst the thumb is placed on'the lever 3-1. By pressing with the thumb on the lever 31, the latter is moved towards the casing 10, the segment 30 turns the wheel 27, and the latter pinion 26 together with the wheel latter, bymeans of the pinion, rotates the fieldvmagnet 11 with a rate of transmission of 1-20, in round figures' The lever is thereupon allowed-to return to its initial position under the action of the spring 33, the ratchet wheel sliding along the pawl 35 so that the other wheels arenotaifected by the return movementof the lever. On

the lever 31 being again operated, the field magnet will be againv given animpulse-for revolving. As the field magnet is approximately of the same length as the. cylindrical portion of the casing 10, the wholeof it will act as a fly-wheelfwhich ppovides fOl'.

The comparatively considerable length of the field magnet results in. a large number of uniformity in running-and driying.

lines of force flowing from one pole piece to the other, and as the armature 'is mounted within the field magnet and is of approximately. the same length, a great number of by a great number of line's of force, held windings on the armature can be intersected 0 compactly. together, and consequently the currentv generated produces a very strong illuminating power of the pocket lamps.

As the casing is cylindrical and provided 5 at the bottom with a portion widened to one The arrangement of the driving means in v the. lower portion of the casing, that is to say, in .the widened'portion, allows of pair are secured with 'their poles of the same sign to the same. pole piece 14, but the poles'of the same sign leave between using1 a high rate of transmission. W atI laim'is:

11.,An e 'ectric pocket lamp comprising a impulse driven field member having a large .mass,-"exterior of'said' armature and whdse inertia will be maintained substantially eonstant during theinterval between successive impulses, and hand-operated impulse mechanism for driving said field. member.

2. An electric pocket lamp-comprising a casing, a stationary elongated armature in said casing, an electric lamp connected to said armature, a cylindricalelongated field member rotatably" mounted within s'aidcasin and around said. armature, and an impu se mechanism mo1 1nted in an enlarged portion of the casing at the end of said armature and field member.

3. An electric pocket lamp comprising a tubular body] portion having an eccentric enlargement at one end, a stationary armar ture mounted in said tubular portion, and a tubular rotatable field member; within the casing surrounding said armature, an impulse gear train, in said enlargement for OTTO cn'rscnnn;

imparting high velocity to saidfieldmem- 

